This invention relates to a method and system for automatically controlling engine speed of a vehicle engine in a turn.
A great number of automobiles are sold with an automatic transmission. When a vehicle with such a transmission enters a turn or curve on a road, a driver of the vehicle generally takes his foot off the accelerator pedal. As a consequence, the engine speed of the vehicle is greatly reduced. When the driver leaves the turn, the driver may then accelerate the engine to thereby increase engine speed. This reduction and then subsequent increase in engine speed reduces vehicle performance due to the time delay associated with the fall and rise of engine speed.
Efforts have been undertaken to enhance vehicle performance of an automatic transmission in a vehicle turn by preventing the automatic transmission from shifting gears under certain circumstances. These efforts to enhance vehicle performance have met with some success. On the other hand, efforts to maintain engine speed in a turn have presented particular design challenges. Indeed, the automatic control of engine speed takes control of the vehicle away from the vehicle driver. Accordingly, a successful management of engine speed during a vehicle turn must accommodate the need for safe vehicle operation without driver assistance and to further account for driver input.
Moreover, there is also a need to manage the demands on the engine from an automated engine speed control with the other systems on the vehicle that require engine power. The vehicle's electrical system, air conditioning system, power steering system, mechanical and frictional loads, hydraulic pump loads and other vehicle systems may all impact engine load and consequently affect performance of the vehicle engine. Therefore, a successful engine control system must accommodate and manage all of these concerns.
A need therefore exists for a technique and system for maintaining an optimal engine speed during a vehicle turn that surmounts the foregoing design challenges.